Fuse holder



Aug. 13, 1957 J. D. KINNEAR, JR

FUSE HOLDER Filed Aug. 11. 1954 INVENTOR JOSA'PH 12. Kmae JR United States Patent FUSE HOLDER Joseph D. Kinnear, J1 Grosse Pointe Woods, Mich.

Application August 11, 1954, Serial No. 449,217

6 Claims. (Cl. 200-133) This invention relates to a fuse holder and more particularly to a fuse holder of the in-the-line type.

It is an object of this invention to provide a fuse holder which is of very simple construction and therefore admirably suited for low-costproduction.

A further object of the invention resides in the provision of an in-the-line fuse holder which is particularly adapted for connecting a single fuse into several circuits so that a single fuse may be arranged to protect a plurality of circuits.

More specifically, the invention contemplates a fuse holder for the cartridge type of fuse in the form of a tubular body in which the fuse is adapted to be inserted. Within each end of the tubular body there is arranged a ring member which is adapted to circumferentially clamp around the ferrule at each end of the fuse. The clamping member is arranged to be contracted into clamping engagement with the ferrule by inserting a locking member into engagement with the clamping member. The locking member which is preferably wedge shaped has a dual function. It locks the fuse within the tubular body and also forms a conductor to which one or more wires may be conveniently soldered or otherwise attached.

In the drawings:

Fig. 1 is a longitudinal sectional view of the fuse holder of this invention shown with a fuse inserted and locked in place therein.

Fig. 2 is a fragmentary end view of the fuse holder.

Fig. 3 is a perspective view of the clamp for the fuse holder and the locking member for the clamp.

Fig. 4 is a plan view of the clamp as seen from the top side thereof. 2

Fig. 5 is a fragmentary sectional view of the fuse holder and the clamp and locking members therefor.

Fig. 6 is a perspective view of a slightly different form of locking member.

Fig. 7 is a perspective view of another modified form of locking member and clamping member.

Fig. 8 is a perspective view of the general type of fuse usable with the fuse holder of this invention.

. Referring to the drawings, there is illustrated a conventional glass cartridge fuse which includes a glass sleeve 10 closed at each end by metallic caps or ferrules 12. The ferrules 12 form the external contacts on the fuse. The fuse holder of this invention is in the form of a cylindrical body 14 formed of an insulating material such as Bakelite. Body 14 is provided with an axially extending bore or recess 16 of cylindrical shape which has a diameter slightly larger than the diameter of ferrules 12 so that the fuse may be readily inserted into body 14 from either end. At each end of body 14 recess 16 is enlarged as at 18 to form circumferential grooves spaced inwardly of each end of the body. Grooves 18 terminate at their axially inner ends in an annular shoulder 20 and at their axially outer ends in an annular shoulder 22. The grooves 18 thus define an annular seat or socket for clamp members 24. Each clamp member 24 is formed of a strip of "ice metal, preferably spring metal, into cylindrical shape with overlapping free ends 26 as shown in Fig. 3.

The overlapping free end portions 26 are cut away as at 28 so that the end portions 26 can be interengaged as .shown whereby both of these end portions will be disposed on the outer surface of the clamp. The overlapping end portions 26 are arranged such that, when these end portions are shifted circumferentially away from each other, the effective diameter of the clamp is decreased; and when these end portions are shifted circumferentially towards each other, the effective diameter of the clamp is increased. At their extreme free edges the end portions 26 are formed into channel members 30. Channels 30 are inclined towards each other in a direction axially of the clamp 24 so that the two channels cooperate with the end portions 26 to provide an arcuate guide around a portion of the clamp which is narrower at one end than at the other end. The body portion 14 is enlarged as at 32 to accommodate the end portions 26 and the channel members 30.

As mentioned above, clamp members 24 are preferably formed of a spring material, and these clamps normally have an outer diameter at least as large as the diameter of groove 18 so that the clamp members can be contracted sufliciently to be inserted through the end of body 14 into groove 18 and thereafter released so that the clamp members will be retained in groove 18 between shoulders 22 and 26. When arranged in grooves 18, these clamp members normally have an inner diameter slightly greater than the outer diameter of ferrules 12. members arranged within grooves 18, the fuse can be slipped into the body 14 from either end thereof and positioned therein so that the ferrule 12 at one end of the fuse is encircled by one clamp member 2 and the ferrule 12 at the other end of the fuse is encircled by the other clamp member 24.

For the purpose of locking the clamp members 24 around the ferrules 12 of the fuse, there is provided a locking member 34 in the form of an arcuate wedge. Member 34 has an arcuate body portion 36 terminating at each side in edges 38 which are inclined towards each other. The inclination of edges 38 corresponds to the inclination of channels 30 so that the wedge 34 can be slipped over clamp 24 with the edges 38 slidably engaging the channels 31). The width of wedge 34 is greater than the circumferential distance between channels 39 on clamp 24 so that, as thewedge 34 is pushed inwardly of body 14, the edges 38 cooperate with the channels 30 to progressively contract the clamp 24 into firm engagement around the ferrules 12. if desired dimples 4! may be formed adjacent the inner ends of channels 30 and the edge 38 may have small recesses 42 formed therein so that, when the wedge 3-4 is fully engaged with the clamp 24, the recesses 42 interengage with the dimples 46) to yieldably hold the wedge 34 in locking position. I have found, however, that if the angle of inclination of the edges 38 and the corresponding angle of inclination of channels 30 is sufficiently small, the friction between the edges 38 and the channels 39 is sufficient to retain the wedge 34 in the locked position with respect to clamp 24. At its outer edge Wedge 34 is formed with a lug 44 preferably provided with bendable ears 4-6 to facilitate attaching a wire 48 to the wedge 34 such as by soldering or other means.

In some applications it might be desirable to use a single fuse to protect several circuits. One of the advantages of the present holder is that such an arrangement can easily be accommodated by simply forming the wedge 34 with a plurality of lugs 44 such as is illustrated in Fig. 4.

In Fig. 7 there is shown a modified wedge and clamp construction. In this embodiment the clamp member 50 Thus, with the clamp is formed as a cylindrical member with spaced apart free end portions return bent into channels 52. Channels 52, like channel 30, are inclined toward one another from the outer to the inner end of the clamp. The cooperating wedge member 54 is generally similar to the wedge member 34 except that wedge member 54 is formed with inwardly turned channel members 56 at its free edges adapted to interengage with the channel members 52 of the clamp 50 so that the clamp 50 is circumferentially contracted when the wedge 54 is engaged therewith and pushed in a direction inwardly thereof. Clamp 50, of course, is arranged to be disposed within the groove 13 of body 14 in the same manner as the clamp previously illustrated. The primary difference between the clamp and wedge arrangements shown in Fig. 3 and in Fig. 7 is that, in the one case (Fig. 3), the end portions of the clamp are shifted circumferentially away from each other by the cooperating wedge member to contract the clamp; and in the other case (Fig. 7), the end portions of the clamp are drawn circumferentially towards each other by the wedge member to contract the clamp.

With either of the constructions shown it will be observed that the fuse can be readily inserted into the tubular body 14 of the fuse holder, and thereafter the clamps with the conductors 48 attached thereto can be engaged with the respective clamps to place the fuse in circuit with the circuit of the wires and rigidly position the fuse within the holder. When it is desired to replace a burned out fuse, it is only necessary to pull out the wedge members from each end of the fuse holder. As the wedge members are released from their respective clamp members, the clamp members expand and enable the ferruled ends of the fuse to pass therethrough.

Thus, it will be seen that I have provided an in-the-line fuse holder which is attractive not only from the standpoint of manufacture but also from the standpoint of installation and use. The fuse holder includes a minimum of parts which are easily assembled. In this connection it will be appreciated that in many applications where cartridge fuses are used, in the automobile industry, for example, the various circuits are preassembled in the form of a harness which is simply installed on the chassis of the automobile when the automobile is assembled. With the fuse holder of this invention it will be observed that the harness may be completely manufactured without the fuse holder body 14 forming a part of the assembly. In other words, with this invention it is only necessary for the manufacturer of the harness to afiix the wedges 34 to the ends of the wires; and when the harness is installed, the harness may be connected with other circuits of the electrical system simply by employing the fuse holder of this invention. In other words, the fuse holder body 14 need not form a part of the harness assembly.

In addition, it will be noted that the construction of the wedge members is such that no complicated wire connection problems are presented when it is desired to use a 11. single fuse for protecting several circuits. A multiple circuit connection can be easily provided because of the form of wire connecting means on the wedge and by reason of the fact that it is not necessary to run the wires into the fuse holder body itself.

I claim:

1. An in-the-line fuse holder for a cylindrical fuse of the type having ferrules at each end thereof comprising a tubular body member having an axial bore extending therethrough, an annular member positioned in said bore adjacent each end of said body, said annular members being circumferentially contractible and being in a normally circumferentially expanded condition, said annular members in said expanded condition having an internal diameter such that the fuse may be passed therethrough, said annular members having circumferentially shiftable free end portions, and a pair of locking members axially inserted one into each end of said body, said locking members engaging with the free end portions of said annular members and adapted to progressively circumferentially shift said free end portions and thereby progressively contract said annular members when the locking members are moved in a direction axially inwardly of the body member from each end thereof, said locking members being provided with means for attaching one or more electrical conductors thereto.

2. The combination set forth in claim 1 wherein said annular members are formed of a resilient material.

3. The combination set forth in claim 2 including means on the free end portions of said annular members forming a pair of guides which converge in a direction axially inwardly of the tubular member.

4. The combination set forth in claim 3 wherein said locking members are wedge shaped in radial projection and have edge portions engageable with said guides.

5. The combination set fort in claim 4 including cooperating means on said annular and locking members engageable to yieldably lock said locking members against axial movement relative to said annular members together.

6. The combination set forth in claim 5 wherein said cooperating means are arranged to engage with one another in response to axial inward movement of said locking members into engagement with said annular members.

References Cited in the file of this patent UNITED STATES PATENTS 347,150 Beebe Aug. 10, 1886 1,047,086 Krantz Dec. 10, 1912 1,076,851 Welshans Oct. 28, 1913 1,566,953 Becker Dec. 22, 1925 1,916,711 Allgeier July 4, 1933 2,692,417 Primich Oct. 26, 1954 FOREIGN PATENTS 535,821 Great Britain Apr. 23, 1941 634,752 Great Britain Mar. 29, 1950 

